All of the YZ stuff came from official sources. There are zero confirmed official sources with any of this, all of this is just created by a bored fan who wanted attention.
EDIT: My intention is not to burst your bubble, but rather just to say that this is just one (or two) fan-made twitter handles that were created 7 months ago. If you do like this kind of stuff, fan-made or otherwise, please check out Unfiction where this kind of stuff is discussed en masse.